1. Field of the Invention
The present invention relates generally to healing of wounds and wound-treatment therapies. More particularly, but not by way of limitation, the present invention relates to fluid-instillation and negative-pressure wound therapies.
2. Background Information
Clinical studies and practice have shown that providing a reduced pressure in proximity to a tissue site augments and accelerates the growth of new tissue at the tissue site. The applications of this phenomenon are numerous, but application of reduced pressure has been particularly successful in treating wounds. This treatment (frequently referred to in the medical community as “negative pressure wound therapy,” “reduced pressure therapy,” or “vacuum therapy”) provides a number of benefits, including faster healing and increased formulation of granulation tissue. Typically, reduced pressure is applied to tissue through a wound insert (e.g., a porous pad or other manifold device). The wound insert typically contains cells or pores that are capable of distributing reduced pressure to the tissue and channeling fluids that are drawn from the tissue. The wound insert can be incorporated into a wound dressing having other components that facilitate treatment, such as, for example, a drape (e.g., adhesive surgical drape). Instillation fluids may be delivered to the wound insert and held in place at the site of the wound, further improving the efficacy of treatment.
In addition, a technique for magnetically tagging stem cells with an iron-containing clinical agent has recently been developed. See Kyrtatos et al., “Magnetic Tagging Increases Delivery of Circulating Progenitors in Vascular Injury,” JACC Cardiovascular Interventions, 2009; 2(8); 794 DOI:10 1016/j.jcin.2009.05.014. Endothelial progenitor cells—a type of cell proven to be important in the vascular healing process—have been tagged with superparamagnetic iron oxide nanoparticles (SPION) and directed to a site of arterial injury using a disc magnet positioned outside the body. SPION has been approved by the U.S. Food and Drug Administration for use in humans, most often to monitor cells in humans using magnetic resonance imaging procedures. Improved delivery and retention of the magnetically-tagged stem cells was observed.
As described herein, it is possible to use magnetically-tagged clinical agents in combination with negative-pressure wound therapy for improved efficacy of wound treatment.